Migrants at the Mexico/US Border

Tijuana, Mexico (CNN) US Customs and Border Protection closed road and pedestrian bridges on Sunday at the San Ysidro port of entry, one of the largest land border crossings between San Diego and Tijuana, Mexico.

As crowds amassed at San Ysidro, around 500 migrants overwhelmed federal and local Mexican police blockades and rushed toward the border, said freelance reporter Alfredo Alvarez, who is in the crowd.